Centrifugal blower rotor



June 15, 1948. A L. J. woLFE CENTRIFUGAL BLOWER RoTon Filed Aug. 16,71946 INVENToR.

Patented June 15, 1948 UNITED STATES 'PATENT OFFICE 2,443,411 l l f CENTRIFUGAL BLOWER ROTOR Lester J Wolfe, Appleton, N. Y.' Application August 16, 1946, Serial No. 691,070

n Y 5 Claims.

This invention relatesv to improvements rin fans or rotors for use in connection with centrifugal' Another object is to provide a fan having a pair of radially extending blade supporting parts, by means of which the blades of the fan may be accurately welded in correct positions to each other and to a hub. It is also an object of this inventon'to provide a fan having a substantially cylindrical hub portion having one end thereof constructed to receive a radially extending collar provided with radial slots formed to transmit power to thesblades, and a radially extending blade supporting plate which may be welded to the collar and which forms a further support for thel blades. Other objects and advantages of this construction will 'appear from the following description and claims.

In the accompanying drawings which illustrate by way of example one embodiment of this invention:

Fig. 1 is an elevation of a blower housing having a fan or rotor embodying this invention arranged therein.

Fig. 2 is 'a central sectional elevation of my improved fan or rotor on an enlarged scale on line 2--2,Fig. 1.

Fig 3 is a fragmentary rear elevation, partly in section, Iof the fan or rotor. i

The fan embodying this invention is primarily intended for use in connection with a blower housing for elevating hay 'and other coarse materials by means of an air blast, through a discharge spout. It is not intended, however, to limit the fan or rotor to a blower 'for this particular purpose, since it will be obvious that fans of this type may be used for other purposes. The fan is illustrated in Fig. 1 as used in a housing 4 having aninlet 5 for air and the material to be handled, and having a discharge spout 6.

The fan or rotor is constructed to be secured to an end of a drive shaft I which is suitably journ-alled in the housing 4, and which may be rotated by any suitable or desired drive means (not shown). y

The fan includes a. hub 9 which may be of any suitable or desired construction..v Preferably,

however, the hub has a substantially cylindrical outer surface, land an inner bore formed to fit the drive shaft 1. The hub of the fan may, for example, be made of a short length of heavy steel tubingand may bevprovided with set screws I or other suitable means for securing the hub to the shaft 1. The hub is of reduced diameter at the end thereof to which the fan is secured, being provided with 'an annular recess I2 in the peripheral surface at one end thereof, and a collar I lI is provided which is preferably in the form of aplate lof steel or othermaterial that can be welded and is of a thickness equal to the'axial length of the recess in the hub. `The collar has ra central hole or bore which'iitsl snugly in the recess I2 and against the annular. shoulder yformed at the end of this recess, as clearly shown in Fig. 2. This vcollar is provided with radially'ex- `tending slots lor recesses, one such slot being prothe adjacent edges yof the hole in the collar and of the end of the shaft may be provided with an annular groove in which the welding may be done as indicated at I1 in Fig. 2. Welding may also b-e done at the opposite face of the collar 'at the outer face of the bushing 9. By means of this welded construction, the collar and hub become a substantially integral part, so that no key `or other securing means are required to connect the hub and collar.

The fan or rot-or also includes a blade supporting Iand reinforcing plate I8 which may be of any desired exterior shape or contour and is preferably also made of a flat metal plate.v The blade supporting plate may, for example, be provided with outwardly extending legs I9 which are provided with radial slots 20 into which portions of the blades I6 may fit. The blade supporting plate preferably fits flush against the endof the drive shaft 1 and against the end of the hub 9 as shown in Fig. 2, and consequently the axial portion of this plate does not have a bore through whichthe shaft 1 extends.

In order to provide a strong and rugged construction, the slots 20 in the blade supporting plate extendonly a part of the. distance from the Youter @pas ofthe, legs 'I9 and themades Icare 79, fwhic-h will-automatically bringithe v`collar in lconcentr/ic relation tc the axis ofthe hub and the collar-inlay then-be welded -to the Vhub in any suityable er desired manner. .The-,bladesupporting and reinforcing plate-iti and .the blades le are thenvittedto the -collar l-l by the interiitting slots of theblades-andofA the supporting plate, and the innenportions-ofthe blades are then inserted --intothe-fradial slotsformedr in thecollar y le, for ,exam-ple by` moving the l supportingplate against the-.end `ofthe collar 9. `may thenbeweldedto the Collard/tin any usual or suitablegmannenior example, by forming a :weld-..aroLmd-the peripheralportion of the collar .andf the portion of.the.supporting plateadjacent ftheretdas `indicated at 2d, Fig 3.

.sired contour. .'describednthe fan may be made .entirely of steel A sc thatallof .the `parts-thereof can be `wel-ded togethen and provide -amplestrength andfreedom from .connections or-joints that maybeprovided at their inner ends with slots into which unslotted portions of the arms I9 of the plate I8 extend, so that the slotted portions of these blades may engage opposite faces of unslotted parts of the blade supporting plate I8. The portions of the blades adjacent to the slots therein and tothe inner portions lof the blades enter the slots in the collaigcand since thecollaris welded to the blade supporting plate, a very secure connection is provided between the blades and the parts of the fan on which they are supported and this connection is of ample strengthrto transmit the power of the drive shaft to theV blades. AThe inner ends of the blades may be arrangedin spaced relation to the hub, but preterably--the blades extend to the hub so that the inner edges of the blades engage -or are in close-'proximity to the peripheral surface of the hub Q. The blade *supporting plate 3v and the-bladesd are; also made-oflflat -rnetal and can be 1punched from a platepr; sheet-by means of` dies, Vor otherwise "cut-so that all of these parts may bek accurately assembled .-,lntthefassembly of the-fan. or rotor, the collar aiirstftted-on the-recessed end Vci the hub The supp orting plate The blades ofthe -fanina-ythen. be. welded to the lsupporti-ng plate-and collar-along the meeting edgesthereof,

as indicated at 25. If the blades are sofforrned :that theinner edges-thereof lie4 againstthe outer Vsurface 4of :the hub member`- 9,` then theseinner .edges of .theblades 4may/.falscheweldedY to the vouter surface `of thehub by means of longitudinally. extending weldsf-Z l ,Fig 3.

.Byineans of .the .construction -described, the

blades .L6 .in .the construction illustrated. are flat, they may, of course, be of. anyothersuitable -or -de- By means of the construction come-loose. .The collar,I 1.4,. together with the sup- .porting` plate, .form .a strong support for the blades .attheY-portion thereof nearest to the axis ...of ythe hub 1.9, .where .the blades and other parts .ofthe fan aresubjectedte the .greatest stresses.

. `At greater. distances from the axis, ybeyond vthe collar .1.4, vthesupporting.plate lalone is sulcient to carry the torque of the driving shaft to .theblades .Beyond ,the bladesupporting plate L8, .the ,blades ,themselvesl have suliicientstrength supporting plate yduring welding. Because of the .drical hub having an annular recess in the peripheral `surfacel at one v.en-d-thereoff a radiallyr outwardly extending collar having an axial ap- --Ylerture into which said recessed end of said hub vplate having coinciding radial slots, and fan .blades extending into said slots and extending yts, aweldsecuring said collar to said hub, a

blade suporting plate arranged in contact with said collar. and the adjacent end of said shaft,

and welded to said collar, said collar and said outwardly from said plate and collar and welded ..to saidplate .and `said collar, and meansfor securing ,said hub ,on ashaft.

2. A. rotary fan formed for mounting on a ydrive shaft .and including A.a substantially `.cylindrical hub having han annular recess .inthe peripheral ...surface at'. onel end. thereof, a, radially outwardly .extending collar.l having an axial .aperture `into ;whichl.said recessed end` of vsaid hubjts, a weld securing said collar to said h ub, a blade support- ,.ing, plate yarranged in contact withsaid 4collar -.,and`theadjacent end of said shaft, andwelded ,coinciding radial slots, andian bladesextending .intosaid slots and extending outwardly 'from said plate.. and collar and welded to said plate and to sai-d collar, said collar and said plate having said.,collar,.,.rneans for securing .sai-dhub on a sha-ft, `thelinnerends oi `said blades being welded ,to said hub.

,3. ,A rotary fan for, mounting on a drive shaft vand including ka substantially cylindrical hub, a A,radially Voutwardly extending collar welded .to .said hub, ablade supporting plate welded to said collar, said collar V,and ,said plate having registerngslots*extending inwardly from the outer edges thereof, a plurality of blades ,havingparts extending, into said .slots and welded to saidplate andsaid collar, and rneansior .securing said collar to a drive shaft.

A. `Arotary fan .according toclaim E'character- .ized in that saidranzblades have slots extending inwardly from the inner ends thereof and lthat the blade supporting plate has slots intheouter .portions only thereof, whereby the slots in the kand Iincludinga substantially cylindrical hub, a

radially .outwardly extending collar welded to said hub and vhaving slots ,therein extending; in- ,wardly from theyperiphery of'saidcollar `toward said hub, A,a blade .supporting plate secured to .saidcollansaid plate having'slots extending inwardlly from the outeredge ,thereof and terminatingradially beyond said collar, said plate beingsecured to .i said collar with the slots in said collarand said plate `in alignment, `the portion loisaid plate whichfis secured to said collar being free from slots, and s a .plurality of .blades having parts extending into saidislotsof said plate and said collar and having the inner portions thereof `slotted to straddl'e the unslotted portions of said plate, said blades being weldedy to vsaid plate and tosaid-collar.

LESTER J. -WOLFE. 

